1. Field of the Invention
This invention relates to fluid couplings. More particularly, it relates to hydraulic couplings used in undersea equipment for oil and gas exploration and production.
2. Description of the Related Art
Many varieties and configurations of hydraulic couplings are known in the art. Examples of various undersea hydraulic coupling members are disclosed in the following United States patents by Robert E. Smith III: U.S. Pat. No. 6,663,144 entitled Seal retainer for undersea hydraulic coupling; U.S. Pat. No. 6,659,425 entitled Male coupling member with improved flow ports; U.S. Pat. No. 6,626,207 entitled Undersea hydraulic coupling with interlocking poppet valve actuators; U.S. Pat. No. 6,575,430 entitled Hydraulic coupling with dovetail seal having multiple radial sealing surfaces; U.S. Pat. No. 6,516,831 entitled Undersea hydraulic coupling with radial seals on probe; U.S. Pat. No. 6,511,043 entitled Female coupling member with recessed flow passages; U.S. Pat. No. 6,474,359 entitled Undersea hydraulic coupling member; U.S. Pat. No. 6,357,722 entitled Undersea hydraulic coupling with guide for valve actuator; U.S. Pat. No. 6,237,632 entitled Undersea hydraulic coupling member with primary and secondary poppet valves; U.S. Pat. No. 6,202,691 entitled Undersea hydraulic coupling with bleed port; U.S. Pat. No. 6,202,690 entitled Pressure balanced undersea hydraulic coupling; and, U.S. Pat. No. 5,469,887 entitled Hydraulic coupling with pressure equalizing valve.
In general, the hydraulic couplings of the prior art have a single inlet and a single outlet for the hydraulic fluid. If multiple flow paths are needed, two or more couplings of the prior art must be used in combination, or, in the alternative, an arrangement of valves may be employed to create multiple flow paths for the fluid. The present invention solves this problem by providing a single coupling having multiple flow paths. One example of an application for a coupling having multiple flow paths is the installation of an hydraulically-powered or hydraulically-controlled device which requires one hydraulic fluid path to be maintained during the installation process and another hydraulic fluid path once it is installed.